. >> well, senator, i agree that an environment of low rates, low interest rates, especially when it p prevails for a long time, and we have had a long period of low interest rates can give rise to behavior that poses threats to financial stability. and therefore we need to be looking at that very carefully. and we are doing so in a very thorough way, i believe. there are a number of things that we are monitoring. measures of asset prices and whether or not they appear to be diverging from historical norms. namely it's hard but trying to spot any asset price bubbles that might be emerging. we're looking at leverage, which build up in leverage can be very dangerous to the financial system and pose stability risks. we're looking at trends in leverage. we're looking at credit growth to see whether or not that has potentially worrisome trends. in addition to that we're looking the particularly through the stress tests at financial institutions and a low interest rate environment. we have to worry about whether or not they're appropriately dealing with interest rate risk ls. we have been